This invention relates to an adjustable post-operative prosthetic socket and, in particular, to a post operative protective socket that can be worn over a bandage and dressing while still providing easy access to the wound.
In U.S. Pat. No. 4,842,608 to Marx, there is described a protective prosthetic socket for post operative use by a transtibial (below the knee) amputee. As noted in the Marx patent, persons who have lost a lower limb can be fitted immediately after surgery with a prosthetic socket to protect the wound during the early stages of rehabilitation. Such amputees are subject to falling because of their initial inability to cope with one limb or simply because the patient forgot that he or she has lost part of a limb and attempts to place weight on the residual limb. These falls can be, at times, dangerous and damaging to the wound and thus extends the rehabilitation period.
After surgery, there is considerable swelling in and about the wound area. The wound is generally dressed and wrapped with a compressive bandage to reduce the swelling. Most post operative protective devices, although custom fitted, will not maintain pressure contact with the residual limb as the swelling subsides and thus fail to provide the restraint. More importantly, these custom fitted devices do not provide easy or ready access to the wound area when the wound or the bandage needs attention.
The Marx patent addresses some, but not all of the problems associated with post operative protective sockets. The Marx device involves three separate parts that are cojoined in assembly using a number of tensioning devices that include a screw jack, a ratchet mechanism and straps adapted to encircle the various component parts of the device. The three pieces are adapted to provide adjustability between parts to accommodate for variations in the residual limb size as the swelling is gradually reduced during the healing process. The Marx socket is rather complex in design and is therefore difficult to properly fit and accurately mount on the residual limb without assistance. The interrelated parts, through usage, can shift out of position in relation to each other and the device therefore will be unable to restrict knee flexion contractures to the degree required during post operative recovery. The Marx device, because of its many mechanical components, does not provide easy access to the wound area, nor does it prepare and shape the residual limb for a more permanent prosthetic device.
Danforth, in U.S. Pat. No. 5,211,667 describes a prosthesis for protecting a residual limb after a lower limb amputation. The device involves an upper shell that is specifically contoured to the patient's residual limb and a lower shell that is telescoped tightly into the upper shell. A stump sock having a flexible strip hanging from its distal end is required to be worn by the user. The flexible strip is passed through a series of holes formed in the sections and is ultimately fastened to the exterior surface of the lower shell to hold the parts in assembly. In the event of a fall, the lower shell is forced upwardly into the upper shell to cushion the impact of the fall. However, this telescoping action can, under certain circumstances, compress the upper shell around the wound area and thus, in the case of a fall producing high impact loading, may actually cause harm rather than prevent it.